Largest rimfire catridge?

[gunsmithcats]

In light of all the crazy potential AW crap, really curious as to what the largest Rimfire cartridge is; I know of the 22 magnum but I was wondering if there's anything bigger, or more devastating.
I'd like to see a EBR in a large rimfire cartridge just to say FU to the lawmakers.
I know Keltec has their RMR in 22 magnum, but it loks like its been shelved for now.

[Gnome]

I'm not sure, but isn't the .17HMR a rimfire cartridge. I Googl'd it, and believe it is. It's a nasty little round either way. Groundhogs/Rabbits tell scary stories to their offspring about it. YouTube it...

[Agustav]

The new .17 Winchester Super Magnum looked promising, but have limited firearm choices chambered for it.

[Renaissance Redneck]

In light of all the crazy potential AW crap, really curious as to what the largest Rimfire cartridge is; I know of the 22 magnum but I was wondering if there's anything bigger, or more devastating.
I'd like to see a EBR in a large rimfire cartridge just to say FU to the lawmakers.
I know Keltec has their RMR in 22 magnum, but it loks like its been shelved for now.

I believe very large caliber rimfires were once used; I'm not really knowledgeable about it, but Googling rimfires might reveal the possibilities, and perhaps even some sources for ammo (though you'd still need the gun!)

As to the new proposed laws, I think one of the AW ban bills now circulating also applies to rimfires (can't remember the bill #). Your 10/22 may become an illegal assault weapon!!!

[ChrisC]

Copied from wikipedia:

In some countries, rimfire cartridges up to at least .32-caliber are still used and even the .44 Henry (a circa 1860 cartridge) is still occasionally offered

[tuolumnejim]

First one I thought of was a Spencer .56 rimfire. Link

[unusedusername]

OP: Are you looking for largest, as in biggest projectile, or largest as in most energy delivered?

[curtru]

I was at a gun shop recently that had a 10 mm Turkish or something like that it was a two prong rimfire. But they had no ammo to show size but looked like a huge chamber.

[nick]

.41 Swiss rimfire! It's rimfire, and it's Swiss, and there are rifles chambered in it. What's not to like?

[westcoast362]

If your line of thought is to use rimfires instead of centerfires in modern guns like 1911's or AW's, it won't work. The brass on a rimfire has to be thin enough for the firing pin to crush it. That limits the amount of pressure the case can take.
Even if you find a loophole they will plug it.
The only options for CA are to change the minds of current lawmakers (unlikely), or elect new ones.

[BigL]

Copied from wikipedia:

In some countries, rimfire cartridges up to at least .32-caliber are still used and even the .44 Henry (a circa 1860 cartridge) is still occasionally offered

Agreed